Malicious PDF — malware analysis report

Static analysis result for SHA-256 2b1ddfb1dadb2c79…

MALICIOUS

PDF

70.9 KB Created: 2021-06-20 14:32:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-07
MD5: 2220e20ccd97370d7bda15614b4e88b1 SHA-1: 47ff6aebe002938d1de9788b197c6509eea327f2 SHA-256: 2b1ddfb1dadb2c794e1359f74eb19aa932c69f845ddb5c38985ad3da7520c0ef
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links to external URLs, many of which point to compromised WordPress uploads or disposable hosting, suggesting a phishing or malware distribution scheme. The document body, though heavily obfuscated, contains text related to downloading Windows 10, which is a common lure for such attacks.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://medvor.ru/uplcv?utm_term=download+windows+10+iso+full+activated PDF link annotation
    • http://kyanite.tv/userfiles/file/ginusededupekukuz.pdfIn PDF document text
    • http://ventilatoryzlin.cz/images/file/xizolu.pdfIn PDF document text
    • http://stigstudiotecnico.it/userfiles/files/saxubezojin.pdfIn PDF document text
    • https://www.blackandwhite-salon.com/wp-content/plugins/super-forms/uploads/php/files/e9e3ee1c2f199e315b5f52e3e9490d99/84203138622.pdfIn PDF document text
    • https://louvre.lv/res/wysiwyg/file/31682693487.pdfIn PDF document text
    • https://ambulatorioveterinariosismondi.eu/file/98939525997.pdfIn PDF document text
    • http://villaturri.it/wp-content/plugins/formcraft/file-upload/server/content/files/1609833b760ee3---mewuxegurexowukevo.pdfIn PDF document text
    • https://www.ideaklinikkadikoy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609bb2060b973---90800406351.pdfIn PDF document text
    • https://stopserv.ru/files/file/52315208265.pdfIn PDF document text
    • https://www.mozartcantat.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160b29a93203d7---51409549346.pdfIn PDF document text
    • http://www.chatanakonci.cz/userfiles/file/woparoderenokokosar.pdfIn PDF document text
    • https://advancedbusiness.co/wp-content/plugins/super-forms/uploads/php/files/d675d7ac3c1c44020484cf966735ca74/63340310312.pdfIn PDF document text
    • https://www.gml.de/wp-content/plugins/formcraft/file-upload/server/content/files/16080c563d31cf---28972117744.pdfIn PDF document text
    • http://queuemanagementsystems.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c631b3b0d78---juzepesenoge.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000da30.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA30 5264 bytes
SHA-256: 0951d4aa9f4f3e88c2864fa00c71e64e7617b7d4910901d88fa3a0278e231770
font_01_sfnt_off0000ec5a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC5A 10156 bytes
SHA-256: 8b7dfe1730cf345816bc813c8d027d38ef6bcabdfb8cbdbcb93fdc62806ea236